The @Implements directive gets the Asp.Net page to implement a specified .NET framework interface. The only single attribute is Interface, helps to specify the .NET Framework interface. When the Asp.Net page or user control implements an interface, it has direct access to all its events, methods and properties.

@Implements Directive

<%@ Implements interface="ValidInterfaceName" %>

interface: The interface to be implemented on the page or user control.

<%@ Implements Interface=”System.Web.UI.IValidator” %>

@ Implements directive to access the six properties of the IWebPart interface.

Web applications are accessed by multiple users. A web site can have an extremely low load for minimum number of client access which provide faster access of the sites or may be heavy load on the site can increase exponentially which can slow down the server as well as access of Sites . Slow access is the most common problem for any web site when it is accessed by a large number of client simultaneously. For resolve this problem we can have used high level of hardware configuration, Load Balancer , High bandwidth but load is not the only reason that make a web site is slow , so we need to provide such kind of mechanism which also provide fast data access and provide performance improvement of web site. Caching provide the solution.

Caching is a technique where we can store frequently used data and Web pages are stored temporarily on local hard disks for later retrieval. This technique improves the access time when multiple users access a Web site simultaneously or a single user accesses a Web site multiple times. Caching for Web applications can occur on the client (browser caching), on a server between the client and the Web server (proxy caching / Reverse Proxy Caching), and on the Web server itself (page caching or data caching).

Maximum time we chose web server to store cached data though it improved the performance but it does not solve our purpose every time. If we consider about load on Web Server we have to consider about the location that when the cached data should store.

ASP.NET provides a mechanism for caching portions of pages, called page fragment caching. To cache a portion of a page, you must first encapsulate the portion of the page you want to cache into a user control. In the user control source file, add an OutputCache directive specifying the Duration and VaryByParam attributes. When that user control is loaded into a page at runtime, it is cached, and all subsequent pages that reference that same user control will retrieve it from the cache.

<!— UserControl.ascx —>

<%@ OutputCache Duration='60'
VaryByParam='none' %>
<%@ Control Language="'C#'" %>

<script runat="server">
protected void Page_Load(Object src, EventArgs e)
{
_date.Text = "User control generated at " +
DateTime.Now.ToString();
}
</script>
<asp:Label id='_date' runat="'server'" />

Here I have user caching on user control, so when ever we used in a page , only partial page will be cached.